help (mdf storage units)

[newbie chippie]

alrght guys i am having a couple of problems with the construction of the veneered mdf storage units you helped me deign, and i need some help urgently.

Problem 1

I had all the panels cut to size and delivered by the merchants, but some panels have a 1mm or so difference in the depth. For example the top and bottom panels are 1mm deeper than the sides.

So should i just use the flush face for the face of the units, and hope the back pulls in enough when screwed on?

Or have i got to some sanding?
Or planing?

Problem 2

I am having trouble getting the sides, tops, and bottoms all square. Some of the side panels have a little bow in them but i am pretty sure that will pull in when the units are all together, and the shelves are in.

How do i make sure the units are perfectly squared before i fix them to together?

Is it alright to construct the units outside first to make sure they are right? I am worrird about the screws not biting enough when i construct them in the room, if i construct them outside first.

all the best newbie

 

[Deluks]

Problem 1

I had all the panels cut to size and delivered by the merchants, but some panels have a 1mm or so difference in the depth. For example the top and bottom panels are 1mm deeper than the sides.

So should i just use the flush face for the face of the units, and hope the back pulls in enough when screwed on?

Or have i got to some sanding?
Or planing?

1mm is nowt really, you can fix them flush to the wall and caulk that (decorators sealant) although planing 1mm off won't be too hard, but you'll kick yerself if you take too much off.

Problem 2

I am having trouble getting the sides, tops, and bottoms all square. Some of the side panels have a little bow in them but i am pretty sure that will pull in when the units are all together, and the shelves are in.

How do i make sure the units are perfectly squared before i fix them to together?

erm, use a square?

Another trick is to measure diagonally corner to corner (bottom left to top right corner, and then bottom right to top left corner. Or if you prefer.... top right to bottom left corner, and then top left to bottom right corner )

When the diagonal measurements are exactly the same for each side then it will be square.

Is it alright to construct the units outside first to make sure they are right? I am worrird about the screws not biting enough when i construct them in the room, if i construct them outside first.

all the best newbie

Screws work both inside and outside
No seriously more in and outs will weaken the hole, as my ex-girlfriend 'Welly-Top Mary' once told me.

Construct them inside, outside you won't have the walls for reference, which they will spend their life attached too.

Have you got a level? at least 2ft long? Most chippies do it by eye anyway. Your brain will know when it looks right.

 

[oilman]

here's a square

http://youtube.com/watch?v=A7RdAQj8nFc

 

[big-all]

if your boards are machine cut when you screw them together providing the panel saw is properly set up they will automaticly pull up fairly square

also you can use the sheet material as a large square providing you use 2 untouched edges

and measuring the diagonal is the best way to square up just keep in mind the discrepancy is only half the difference on the diagonal and 1/3 in a strait line

so if the diagonals are say 583 and 589 you only have to move them 3 mm closer so they are both on 586

and if you done nowt about it you would only be around 2mm out on the vertical
so as you see its a very accurate easy way to square a cabinate or any frame work